Final answer:
The binding of SRP to the N-terminal signal sequence on a protein halts elongation until the complex attaches to the SRP receptor on the ER, after which protein synthesis resumes and the protein is processed for cellular functions.
Step-by-step explanation:
Binding of the SRP (signal recognition particle) to the N-terminal ER sequence on a protein slows down polypeptide elongation until the SRP binds to the SRP receptor on the ER. This process is critical for the targeting of proteins to the endoplasmic reticulum (ER) for proper processing and transportation.
Once the ribosome-SRP complex finds and binds with the SRP receptor on the rough ER (RER) membrane, the SRP detaches and translation elongation resumes. The growing polypeptide can then continue to elongate into the RER cisterna, eventually leading to cleavage of the hydrophobic signal peptide by a signal peptidase. This intricate coordination ensures the proteins are correctly synthesized and directed to their function within the cell.